Salvage Therapy for Local Progression following Definitive Therapy for Skull Base Chordomas: Is There a Role of Stereotactic Radiosurgery?

Carbon Ion Radiotherapy: An Evidence-Based Review and Summary Recommendations of Clinical Outcomes for Skull-Base Chordomas and Chondrosarcomas

Skull-base chordoma and chondrosarcoma are rare radioresistant tumors treated with surgical resection and/or radiotherapy. Because of the established dosimetric and biological benefits of heavy particle therapy, we performed a systematic and evidence-based review of the clinical outcomes of patients with skull-base chordoma and chondrosarcoma treated with carbon ion radiotherapy (CIRT). A literature review was performed using a MEDLINE search of all articles to date. We identified 227 studies as appropriate for review, and 24 were ultimately included. The published data illustrate that CIRT provides benchmark disease control outcomes for skull-base chordoma and chondrosarcoma, respectively, with acceptable toxicity. CIRT is an advanced treatment technique that may provide not only dosimetric benefits over conventional photon therapy but also biologic intensification to overcome mechanisms of radioresistance. Ongoing research is needed to define the magnitude of benefit, patient selection, and cost-effectiveness of CIRT compared to other forms of radiotherapy.

Endoscopic endonasal approach for loco-regional recurrent clivus chordomas

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EEA represents an ideal approach for loco-regional recurrent CCs.

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EEA is well tolerated, with preservation of patients QoL.

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EEA can be considered for patients with perspectives of adjuvant therapies.

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Otherwise, EEA can be considered only in selected cases with a palliative aim.

Chordoma: Current status, problems, and future directions

Chordoma is a rare tumor that occurs along the axial spine in pediatrics and adults, with an incidence of approximately 350 cases per year in the United States. While typically described as slow-growing, many patients will eventually develop loco-regional relapse or metastatic disease with few treatment options. Despite numerous efforts over the last 10+ years, effective treatments for patients are lacking. As subtypes of chordoma are identified and described in more detail, further knowledge regarding the natural history of each type, tumor location, age differences, genomic variability, and an overall better understanding of chordoma may be the key to developing meaningful clinical trials and effective therapies for patients with chordoma.

Surgical Management of Skull Base and Spine Chordomas

OPINION STATEMENT

Management of chordoma along the cranial-spinal axis is a major challenge for both skull base and spinal surgeons. Although chordoma remains a rare tumor, occurring in approximately 1 per 1 million individuals, its treatment poses several challenges. These tumors are generally poorly responsive to radiation and chemotherapy, leading to surgical resection as the mainstay of treatment. Due to anatomic constraints and unique challenges associated with each primary site of disease, gross total resection is often not feasible and is associated with high rates of morbidity. Additionally, chordoma is associated with high rates of recurrence due to the tumor's aggressive biologic features, and postoperative radiation is increasingly incorporated as a treatment option for these patients. Despite these challenges, modern-day surgical techniques in both skull base and spinal surgery have facilitated improved patient outcomes. For example, endoscopic endonasal techniques have become the mainstay in resection of skull base chordomas, improving the ability to achieve gross total resection, while reducing associated morbidity of open transfacial techniques. Resection of spinal chordomas has been facilitated by emerging techniques in preoperative imaging, intraoperative navigation, spinal reconstruction, and radiotherapy. Taken collectively, the treatment of chordoma affecting the skull base and spinal requires a multidisciplinary team of surgeons, radiation oncologists, and medical oncologists who specialize in the treatment of this challenging disease.

Advances in the management of primary bone sarcomas of the skull base

Skull base primary malignancies represent a heterogeneous group of histologic diagnoses and sarcomas of the skull base are specific malignant tumors that arise from mesenchymal cells and can be classified by site of origin into bony and soft tissue sarcomas. The most common bony sarcomas include: chondrosarcoma, osteosarcoma, chordoma, Ewing's sarcoma. Given the relative rarity of each histologic diagnosis, especially in the skull base, there is limited published data to guide the management of patients with skull base sarcomas. An electronic search of the literature was performed to obtain key publications in the management of bony sarcomas of the skull base published within the last decade. This article is thus a review of the multi-disciplinary management principles of primary bony sarcomas of the skull base. Of note, there have been several recent advancements in the realm of skull base sarcoma management that have resulted in improved survival. These include advances in: imaging and diagnostic techniques, surgical techniques that incorporate oncologic surgical principles, conformal radiation paradigms and targeted systemic therapies. Early access to coordinated multi-disciplinary subspecialty care immediately at suspicion of diagnosis has further improved outcomes. There are several ongoing trials in the realms of radiation therapy and systemic therapy that will hopefully provide further insight about the optimal management of bony sarcomas of the skull base.